This seems a simple question, so I hope its a simple answer. I am plotting my points and fitting a linear model, which I can do OK. I then want to plot some summary statistics, for example the R Squared value, on the plot also. I can only seem to get the R Squared value at the command line. Any advice; do I need to be looking at ggplot or anything else? Thanks in advance.
#Does the plot plot(df$VAR1, df$VAR2) #Adds the line abline(lm(df$VAR2~df$VAR1), col="red") #Shows stats on command line summary(lm(df$VAR2~df$VAR1))
You can abuse
legend() because it has the handy logical placement:
R> DF <- data.frame(VAR1=rnorm(100), VAR2=rnorm(100))
R> with(DF, plot(VAR1, VAR2))
R> abline(fit <- lm(VAR2 ~ VAR1, data=DF), col='red')
R> legend("topright", bty="n", legend=paste("R2 is",
+ format(summary(fit)$adj.r.squared, digits=4)))
bty="n" suppresses the box, and you need
format() to shorten the display. Other
text() is good, as are arguments
text function places text into the current plot, it is one option for adding the r-squared value to a plot. Also look at the
grconvertY functions for ways to find the location to place the text.
emptyspace functions in the
plotrix package may also help.